Atomistic modeling of electron-phonon coupling and transport properties in<mml:math xmlns:mml="http://www.w3.org/1998/Math/MathML" display="inline"><mml:mi>n</mml:mi></mml:math>-type [110] silicon nanowires

Abstract

Using a $s{p}^{3}{d}^{5}{s}^{\ensuremath{\ast}}$ tight-binding model for electrons and a valence force-field model for phonons, we study the transport properties of [110]-oriented silicon nanowires including all electron-phonon interactions. Using a full resolution of the Boltzmann transport equation, the low-field mobility is calculated and its dependence on the temperature, density of electrons, and size of the nanowires is investigated. We predict that, as a result of strong quantum confinement, (1) electrons couple to a wide and complex distribution of phonon modes and (2) the mobility has a nonmonotonic variation with wire diameter and is strongly reduced with respect to the bulk.